Manufacture of catalysts



Patented Feb. 16, 1943 UNITED STATE MANUFACTURE OF CATALYSTS Vladimir Ipatiei'f and Herman Pines, Chicago, 111., 'assignors to Universal Oil Products Company, Chicago, 11]., a corporation of Delaware No Drawing- Application June 9,1939,

- Serial N0. 278,326

15 Claims.

This application is a continuation-impart of our co-pending application Serial No. 103,391, filed September 30, 1936.

This invention relates particularly to the manorganic reactions, including those involving different classes of hydrocarbons.

More specifically, the invention is concerned with the manufacture of composite catalysts in which a relatively active ingredient, such as a heavy metal salt, is incorporated into a porous granular and adsorptive carrier so. that the catalyst particles produced resist disintegration and agglomeration in various types of vapor, liquid and mixed phase catalytic operations involving organic compounds.-

=In one specific embodiment, the present invention comprises the manufacture of catalysts for usein organic reactions by impregnating relatively inert granular materials with substantially anhydrous aluminum chloride.

The use of aluminum chloride in organic reactions, and particularly in reactions involving the various groups of hydrocarbon i well known in the art. For the sake of indicating certain types of reaction in which the present prepared, catalysts can be employed the following brief summary is given of some typical reactions in which aluminum chloride is employed as a catalyst or condensing agent:

1. Aromatic hydrocarbons can be alkylated with alkyl halides according to the following typical equation:

Benzol Methyl Toluene hloride CQHE. CH.C H5

CsH5.CH.CuHs

Tetraphenyl ethane ctmcn'm CIHICHBI' Stilbene bromide Benzol 4 3. Using aromatic hydrocarbons and acid chlorides, ketones can be prepared according to the following typical equation:

A101; CeHs CHsC OCl -r Ca'HaC O.CHa+HCl Benzol Acetyl chloride 4. The use of aluminum chloride makes possible the preparation of aldehydes by reacting substituted benzenes with carbon monoxide and Acetophenone ufacture of catalysts useful in various types of hydrogen chloride according to the-following simple equation:

5. Organic acids can be prepared from aromatic hydrocarbons by the action of carbonyl chloride upon the aromatic hydrocarbons as shown below:

Benzoic acid gasoline distillates, and also under more moderate conditions of treatment for the purification of these distillates by causing the polymerization of the more reactive aromatic constituents. In the case of complicated hydrocarbon oil mixtures, such as the various fractions produced in the distillation and cracking of petroleum and other hydrocarbon oils it is diificult to follow the exact course of the various reactions which take place when aluminum chloride is employed. However,

.they may be grouped generally under the terms polymerization, alkylation, and condensation. Aluminum chloride is also serviceable in efiect- 'ing isomerization reactions, such as for example the isomerization of hexamethylene to methylcyclopentane, and the isomerization of normal parafiin-hydrocarbon into isomeric'forms.

In efiecting various reactions with granular and substantially anhydrous aluminum chloride catalysts there are some difliculties encountered C., so that above this point it must be utilized in vapor-phase. Furthermore, it is apparent that during the progress of various organic reactions in which the chloride is employed intermediate compounds of a metallo-organic character are formed which frequently possess fluid or semi--' By the development of more complicated reacfiuid' properties which cause a running together of the original particles of catalysts so that less 81111806 i exposed and the reactions are slowed up. Frequently after the use of originally finely divided and granular anhydrous aluminum chloride in such reactions, for example, after the treatment of cracked gasoline, or after the al kylption of aromatic and other types of hydro- 1 carbons with olefins, the catalyst is transformed materials which inay be used alternatively but 20 obviously not with exactly equivalent results on account of variations in adsorptive capacity include activated carbons, various silicates and siliceous materials such as fullers earth, clays, both raw and acid treated, diatomaceous and infusorial earths, granular pumice, and crushed porous porcelain. In fact practically any material which is substantially unreactive with the aluminum chloride so that the desired stable properties of the catalyst granules are assured,

- maybe employed. Of the supports mentioned activated carbons, diatomaceous earths, and pumice are particularly serviceable.

Ordinarily the method of preparation of the present preferred types of catalysts is to mix a granular or powdered adsorbent with anhydrous aluminum chloride and then heat the mass under elevated temperatures and pressures until the chloride has been adsorbed into the pores of the adsorbent. The proportions of adsorbent'carrier' 40 and aluminum chloride may be varied as desired to make catalyst composites of varying activity. In the case of properly activated granular carbons or chars, it has been iound possible and practical to make stable catalysts resistant to 45 disintegrating influences by using approximately equal parts by weight of adsorbent carbon and anhydrous aluminum chloride. Such proportions, after thorough mechanical mixing, are placed in a pressure vessel, which is preferably lined with glass, a small amount of hydrogen chloride is added,'the vessel is brought up to a pressure of approximately 25 atmospheres by the introduction or hydrogen and heated at a temperature of approximately 250 C. for several hours. After such a treatment of the original mix the product obtained is dry and granular, the aluminum chloride apparently having disappeared, though it is actually present in the pores and on the surface of the carbon as evidenced by the violent reaction of the granules with water and the catalytic. activity in organic reactions.

Other analogous catalyst composites may be made by employing substantially the same procedure in connection with other porous adsorbents. Obviously the amount of aluminum chloride used will depend upon the adsorptive capacity or the material employed and similarly the temperature and pressure employed during the impregnation may be varied to produce the best results in any given instance. v

Catalysts of the present character may be emplayed in liquid .phase organic reactions with substantially no tendency for the original particles to run together clue to the formation of in- 5 aids and gases.

asnass tel-mediate sludge-like products, so that much larger quantities of material may be treated before the catalyst has lost its activity. Another advantage resides in the fact that the adsorbed aluminum chloride will remain in place without volatilization at considerably higher temperatures than its normal sublimation point, when vapors of reacting compounds are passed over a stationary granular bed of catalyst. This permits the utilization of the catalysts in the vapor phase treatment of gasoline boiling range cracked distillates for their refining, either as they are produced at the cracking plant or from rerun stills. As an explanation of the observed fact that cata- 5 lysts of the present character maintain their activity over considerably longer periods than ordinary granular anhydrous -aluminum chloride, it is probable that the intermediate addition products and heavy carbonaceous by-products are adsorbed by the activated carbon up to their point of saturation so that the particles remain discrete and show a minimum tendency to adhere over unusually long periods of service.

The term activated carbon as used in the present specification, is intended to include any type "of prepared carbon or carbonaceous material which is more or less granular and possessed of good porosity and structural strength and which has been prepared by general steps involvmg the removal of adsorbed'materials from granular carbonaceous materials such as cocoanut char, wood char, and various varieties of coke by mineral acids and by the controlled heating, preferably under vacuum, to expel adsorbed liq- It is recognized that various forms of active granular chars will vary considerably in adsorptive capacity so that therefore the properties of catalysts prepared in accordance with the present invention will vary both in respect to the amount of anhydrous metal halides which they are able to absorb and in respect to the periods of service in which they are able to maintain a practical activity in diflerent organic reactions. e

The granular catalysts may also be readily utilized in the polymerization of normally gaseous olefins such as those present in the hydrocarbon gas mixtures produced incidental to the crackingof heavy hydrocarbon oils to produce light motor fuel.

While the present process is particularly applicable to the impregnation of relatively inert porous adsorbents with aluminum chloride, it is iound utilizable in connection with other types of catalysts which function similarly to aluminum chloride such as, :tor example, zirconium chloride, ferric chloride, and others. When using these materials, the proportions of carrier and active catalyst will obviously be varied to produce optimum results.

As specific examples of the manufacture of catalyst comprised within the scope of the present invention, the following are given although not with the intention of limiting its scope in exact correspondence therewith.

Example I 100 part by weight of an activated carbon and 100 parts by weight of anhydrous aluminum chloride were thoroughly mixed in a dry atmosphere and then placed in a pressure vessel lined with glass to, avoid corrosion.

hydrogen chloride ga wa introduced equal to 5% by weight of the total mix and the pressure was then raised to a total of 25 atmospheres by An amount oft changed n-butane.

2,311,232 the introduction of substantially dry hydrogen.

The vessel was heated to a temperature '0! 250 C. and the contents mechanically agitated for a periodpf three hours. The product had the general appearance of granular carbon but was somewhat more gray than black. The particles were entirely homogeneous in appearance and gave a vigorous evolution of heat when contacted with water. a

The above catalyst was used to 'isomerize nbutane. 'The vapors of this hydrocarbon containing about 2% by weight of hydrogen chloride were passed through a granular mass of the catalyst at a temperature of about 200 C., a pressure of 650 lbs. per square inch and a moderate space' velocity. It was found that the exit gases contained 53% of isobutane, 3% of propane, 8% of hydrocarbons of more than carbon atoms to the molecule, and the balance un- Compared with an equivalent weight of ordinary granular anhydrous aluminum chloride, the prepared catalyst could be used approximately four times as long before the gradual deposition of carbonaceous residues and by-products rendered the action of the adsorbed aluminum chloride ineffective.

The catalyst, prepared as described above was also utilized in a cracking plant operating upon a gas oil produced from a Mid-Continent crude and havinga gravity of 33 A. P. I. The vapors of the gas oil were preheated to a temperature of 400 C. and passed over a catalyst before entering separating and fractioriating equipment.

Approximately the same yield of 400 E. P. gasoline was obtained as in ordinary pressure cracking without catalyst, that is, 65% by volume of.

the charging stock, and in addition the product required substantially no treatment as produced other than stabilizing to the proper vapor pressure.

As an example of the use of the composite aluminum chloride catalyst to polymerize normally gaseous olefins, a stabilizer reflux from a cracking plant which contained approximately 30% of higher olefins, including propylene and the butenes, was passed over the granular catalyst at a temperature of 85 C.,- and there was produced by this operation approximately eight gallons of liquid polymer per 1000 cubic feed of the entering gas mixture. The liquid products comprising the polymers and adsorbed low boiling paraflins boiled within the range of 40 to 205 C. and were suitable in all respects for use as motor fuel in internal combustion engines.

The catalyst was also utilizable in alkylation reactions, and as an example the compound isobutane was alkylated by isobutene at a temper-'- ature of approximately C. in the presence of about by weight of a granular composite material which was maintained in suspension in the isobutane by mechanical agitation while a stream of isobutene containing"a small percentage of hydrogen chloride was gradually introduced. The introduction of the olefin was continued until approximately equal parts by weight of paraflin and olefin had reacted, when the process was stopped and the liquid alkylated products decanted and recovered. This operation was repeated approximately ten times before the gradual deterioration of the catalyst rendered it ineffective from a practical standpoint. A similar result was obtained when a mixture of the isobutane and isobutene was pumped over a bed of the granular catalyst under controlled temperature conditions.

Example II minum chloride, and placed in a, pressure vessel lined with glass to avoid corrosion. 4% by weight of hydrogen chloride gas was introduced and the contents of the vessel were placed under a pressure of 25 atmospheres by the introduction of dry hydrogen. After heating the vessel for a period of three hours at a temperature of approximately 250 C, during agitation, it was found that the aluminum chloride was exactly adsorbed on the diatomaceous earth so that an apparently dry material was formed.

, The above prepared catalyst was used in isomerization, cracking, and various other types of hydrocarbon conversion reactions, and functioned in substantially the same manner as the catalyst of Example I althoughsomewhat larger amounts were required to compensate for the smaller percentage of aluminum chloride.

Example III parts by weight of pumice was mixed with 32 parts of substantially anhydrous aluminum chloride and heated in a pressure vessel at 250 C. under 25 atmospheres of hydrogen pressure in the presence of 4-5% by weight of hydrogen chloride gas as in the two preceding examples. The particle were dry and could be utilized in substantially the same types of reactions as the catalysts of Example II.

Example IV 82 parts by weight of granular porous porcelain sized to approximately 10-20 mesh were heated with 18 parts by weight of aluminum chloride at a temperature of 260 C. under a hydrogen pressure of 30 atmospheres in the presence of 4% by weight of hydrogen chloride gas. After 4 hours heating the particles of the porcelain were dry and were tried inthe various types of-c'onversion reactions in the same general manner as outlined in Example I, with results in proportion to the amount of aluminum chloride present.

We claim as our invention.

l.' A process for the manufacture of catalysts suitable for accelerating reactions among organic compounds, which comprises impregnating a solid adsorbent with anhydrous aluminumchloride under superatmospheric pressure and while the adsorbent is at a temperature above the vaporization point of the aluminum chloride.

2. A method for producing a, catalyst for accelerating reactions among organic compounds which comprises impregnating a solid adsorbent with a readily volatilizable anhydrous catalytic metallic halide while the adsorbent is at a temperature above the vaporization point of the halide and under superatmospheric pressure.

3. The process as defined in claim 1 further characterized in that the adsorbent is impregnated with the aluminum chloride in the pres-. ence of hydrogen chloride.

4. The process as defined in claim 1 furthernated with the aluminum chloride in the presence of hydrogen chloride and hydrogen.

6. The process as defined in claim 2 further characterized in that the adsorbent is impregcharacterize of hydrogen chloride.

7. The process as defined in claim 2 further ganic compounds, which comprises impregnating a granular adsorbent with vapors of a metal halide selected from the group consisting of characterized in that the adsorbent is impreg- .nated with the metallic halide in the presence I of hydrogen.

8. The pr ess as defined in claim 2 further in that the adsorbent is impregnated with the metallic halide in the presence of hydrogen chloride and hydrogen. 1

9. A process for the manufacture of catalysts suitable for accelerating reactions among organic compounds, which comprises impregnating a solid adsorbent with anhydrous aluminum chloride while the adsorbent is at a temperature above the vaporization point of said aluminum chloride and under super-atmospheric pressure, said impregnation being effected in an atmosphere substantially free of hydrocarbons.

10. A method for producing a'catalyst ior accelerating reactions among organic compounds which comprises impregnating a solid adsorbent with a readily volatilizable anhydrous catalytic metallic halide-while thehadsorbent is at. a temperature above the vaporization point of the halide and under superatmospheric pressure, said impregnation being effected in an atmosphere substantially free of hydrocarbons.

11. A process for the manufacture of catalysts suitable for accelerating reactions among organic compounds, which comprises impregnating a granular adsorbent with a metal halide selected'irom the group chloride; zirconium chloride, and ferric chloride while the adsorbent is at a temperature above the vaporization pointoi said metal halide and under superatmospheric pressure, said impregnation being effected in an atmosphere substantially tree of hydrocarbons.

12. A process for the manufacture of catalysts suitable for accelerating reactions among orconsisting of aluminumaluminum chloride, zirconium chloride, and forric-chloride while the adsorbent is at temperature above 200 C. and under superatmospheric pressure. of the order of 25 atmospheres,-said impregnation being eflected in an atmosphere substantially free of hydrocarbons.

13. A process for the manufacture of catalysts I suitable for accelerating reactions among organic compounds, which comprises impregnating a granular adsorbent with vapors of aluminum chloride while the adsorbent is at temperature above 200 C. and under superatmosphericpressure of the order of 25 atmospheres, said impregnation being, effected in an atmosphere substanv tially free 01' hydrocarbons.

14. A process for the manufacture of. catalysts suitable for accelerating reactions among organic compounds which comprises impregnating a granular activated carbon with anhydrous aluminum chloride while the activated carbon is at a temperature above vaporization point of said aluminum chloride and under superatmospheric pressure, said impregnation being eflected in an atmosphere substantially free of hydro-v carbons.

15. A process for the manufacture 0! catalysts suitable for accelerating reactions among organic compounds, which comprises impregnating a granular activated carbon with vapors ot anhydrous aluminum chloride while the activated carbon is at temperature above 200 C, and under superatmospheric pressures oi the order of 25 atmospheres, said impregnation being effected in an atmosphere substantially free of hydro-- carbons.

VLADIMIR IPA'I'IEFF. HERMAN PINES. 

